/* CommandLMR.java
 * =========================================================================
 * This file is part of the JLaTeXMath Library - http://forge.scilab.org/jlatexmath
 *
 * Copyright (C) 2018 DENIZET Calixte
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * A copy of the GNU General Public License can be found in the file
 * LICENSE.txt provided with the source distribution of this program (see
 * the META-INF directory in the source jar). This license can also be
 * found on the GNU website at http://www.gnu.org/licenses/gpl.html.
 *
 * If you did not receive a copy of the GNU General Public License along
 * with this program, contact the lead developer, or write to the Free
 * Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 *
 * Linking this library statically or dynamically with other modules
 * is making a combined work based on this library. Thus, the terms
 * and conditions of the GNU General Public License cover the whole
 * combination.
 *
 * As a special exception, the copyright holders of this library give you
 * permission to link this library with independent modules to produce
 * an executable, regardless of the license terms of these independent
 * modules, and to copy and distribute the resulting executable under terms
 * of your choice, provided that you also meet, for each linked independent
 * module, the terms and conditions of the license of that module.
 * An independent module is a module which is not derived from or based
 * on this library. If you modify this library, you may extend this exception
 * to your version of the library, but you are not obliged to do so.
 * If you do not wish to do so, delete this exception statement from your
 * version.
 *
 */

package com.himamis.retex.renderer.share.commands;

import java.util.ArrayList;

import com.himamis.retex.renderer.share.Atom;
import com.himamis.retex.renderer.share.AtomConsumer;
import com.himamis.retex.renderer.share.BigDelimiterAtom;
import com.himamis.retex.renderer.share.FencedAtom;
import com.himamis.retex.renderer.share.MiddleAtom;
import com.himamis.retex.renderer.share.RowAtom;
import com.himamis.retex.renderer.share.SymbolAtom;
import com.himamis.retex.renderer.share.TeXParser;
import com.himamis.retex.renderer.share.exception.ParseException;

public class CommandLMR {

	public static class CommandLeft extends Command {

		Atom left;
		ArrayList<MiddleAtom> middles;
		RowAtom base;

		@Override
		public void add(TeXParser tp, Atom a) {
			if (left == null) {
				left = a;
				base = new RowAtom();
			} else {
				base.add(a);
				if (a instanceof MiddleAtom) {
					if (middles == null) {
						middles = new ArrayList<>();
					}
					middles.add((MiddleAtom) a);
				}
			}
		}

		@Override
		public RowAtom steal(TeXParser tp) {
			final RowAtom ra = base;
			base = new RowAtom();
			return ra;
		}

		@Override
		public Atom getLastAtom() {
			return base.getLastAtom();
		}

		void close(TeXParser tp, Atom right) {
			if (left instanceof BigDelimiterAtom) {
				left = ((BigDelimiterAtom) left).delim;
			}
			if (right instanceof BigDelimiterAtom) {
				right = ((BigDelimiterAtom) right).delim;
			}

			Atom a;
			if ((left instanceof SymbolAtom) && (right instanceof SymbolAtom)) {
				a = new FencedAtom(base.simplify(), (SymbolAtom) left, middles,
						(SymbolAtom) right);
			} else {
				a = new RowAtom(left, base.simplify(), right);
			}

			tp.closeConsumer(a);
		}
	}

	public static class CommandMiddle extends Command {

		@Override
		public boolean init(TeXParser tp) {
			tp.close();
			return true;
		}

		@Override
		public void add(TeXParser tp, Atom middle) {
			tp.pop(); // remove this from the stack
			final AtomConsumer ac = tp.peek();
			if (!(ac instanceof CommandLeft)) {
				throw new ParseException(tp, "\\middle doesn't match \\left");
			}
			ac.add(tp, new MiddleAtom(middle));
		}
	}

	public static class CommandRight extends Command {

		@Override
		public boolean init(TeXParser tp) {
			tp.close();
			return true;
		}

		@Override
		public void add(TeXParser tp, Atom close) {
			tp.pop(); // remove this from the stack
			final AtomConsumer ac = tp.peek();
			if (!(ac instanceof CommandLeft)) {
				throw new ParseException(tp, "\\right doesn't match \\left");
			}
			((CommandLeft) ac).close(tp, close);
		}
	}
}
